Merge pull request #14362 from charleskorn/charleskorn/sum-infinity

This commit is contained in:
Ganesh Vernekar 2024-07-03 01:05:03 -04:00 committed by GitHub
commit 3d54bcc018
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4 changed files with 118 additions and 4 deletions

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@ -993,10 +993,14 @@ func funcTimestamp(vals []parser.Value, args parser.Expressions, enh *EvalNodeHe
func kahanSumInc(inc, sum, c float64) (newSum, newC float64) {
t := sum + inc
switch {
case math.IsInf(t, 0):
c = 0
// Using Neumaier improvement, swap if next term larger than sum.
if math.Abs(sum) >= math.Abs(inc) {
case math.Abs(sum) >= math.Abs(inc):
c += (sum - t) + inc
} else {
default:
c += (inc - t) + sum
}
return t, c

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@ -0,0 +1,81 @@
// Copyright 2015 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package promql
import (
"fmt"
"math"
"testing"
"github.com/stretchr/testify/require"
)
func TestKahanSumInc(t *testing.T) {
testCases := map[string]struct {
first float64
second float64
expected float64
}{
"+Inf + anything = +Inf": {
first: math.Inf(1),
second: 2.0,
expected: math.Inf(1),
},
"-Inf + anything = -Inf": {
first: math.Inf(-1),
second: 2.0,
expected: math.Inf(-1),
},
"+Inf + -Inf = NaN": {
first: math.Inf(1),
second: math.Inf(-1),
expected: math.NaN(),
},
"NaN + anything = NaN": {
first: math.NaN(),
second: 2,
expected: math.NaN(),
},
"NaN + Inf = NaN": {
first: math.NaN(),
second: math.Inf(1),
expected: math.NaN(),
},
"NaN + -Inf = NaN": {
first: math.NaN(),
second: math.Inf(-1),
expected: math.NaN(),
},
}
runTest := func(t *testing.T, a, b, expected float64) {
t.Run(fmt.Sprintf("%v + %v = %v", a, b, expected), func(t *testing.T) {
sum, c := kahanSumInc(b, a, 0)
result := sum + c
if math.IsNaN(expected) {
require.Truef(t, math.IsNaN(result), "expected result to be NaN, but got %v (from %v + %v)", result, sum, c)
} else {
require.Equalf(t, expected, result, "expected result to be %v, but got %v (from %v + %v)", expected, result, sum, c)
}
})
}
for name, testCase := range testCases {
t.Run(name, func(t *testing.T) {
runTest(t, testCase.first, testCase.second, testCase.expected)
runTest(t, testCase.second, testCase.first, testCase.expected)
})
}
}

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@ -511,10 +511,39 @@ load 10s
data{test="ten",point="b"} 8
data{test="ten",point="c"} 1e+100
data{test="ten",point="d"} -1e100
data{test="pos_inf",group="1",point="a"} Inf
data{test="pos_inf",group="1",point="b"} 2
data{test="pos_inf",group="2",point="a"} 2
data{test="pos_inf",group="2",point="b"} Inf
data{test="neg_inf",group="1",point="a"} -Inf
data{test="neg_inf",group="1",point="b"} 2
data{test="neg_inf",group="2",point="a"} 2
data{test="neg_inf",group="2",point="b"} -Inf
data{test="inf_inf",point="a"} Inf
data{test="inf_inf",point="b"} -Inf
data{test="nan",group="1",point="a"} NaN
data{test="nan",group="1",point="b"} 2
data{test="nan",group="2",point="a"} 2
data{test="nan",group="2",point="b"} NaN
eval instant at 1m sum(data{test="ten"})
{} 10
eval instant at 1m sum by (group) (data{test="pos_inf"})
{group="1"} Inf
{group="2"} Inf
eval instant at 1m sum by (group) (data{test="neg_inf"})
{group="1"} -Inf
{group="2"} -Inf
eval instant at 1m sum(data{test="inf_inf"})
{} NaN
eval instant at 1m sum by (group) (data{test="nan"})
{group="1"} NaN
{group="2"} NaN
clear
# Test that aggregations are deterministic.

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@ -355,10 +355,10 @@ load 10m
histogram_stddev_stdvar_7 {{schema:3 count:7 sum:Inf z_bucket:1 buckets:[0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 ] n_buckets:[0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 ]}}x1
eval instant at 10m histogram_stddev(histogram_stddev_stdvar_7)
{} NaN
{} Inf
eval instant at 10m histogram_stdvar(histogram_stddev_stdvar_7)
{} NaN
{} Inf
# Apply quantile function to histogram with all positive buckets with zero bucket.
load 10m